Skyrmionic magnetization configurations at chiral magnet/ferromagnet heterostructures

We consider magnetization configurations at chiral magnet (CM)/ferromagnet (FM) heterostructures. In the CM, magnetic skyrmions and spin helices emerge due to the Dzyaloshinskii-Moriya interaction, which then penetrate into the adjacent FM. However, because the non-uniform magnetization structures are energetically unfavorable in the FM, the penetrated magnetization structures are deformed, resulting in exotic three-dimensional configurations, such as skyrmion cones, sideways skyrmions, and twisted helices and skyrmions. We discuss the stability of possible magnetization configurations at the CM/FM and CM/FM/CM hybrid structures within the framework of the variational method, and find that various magnetization configurations appear in the ground state, some of which cause nontrivial emergent magnetic field.